Personal audio devices, including wireless telephones, such as mobile/cellular telephones, cordless telephones, mp3 players, and other consumer audio devices, are in widespread use. Such personal audio devices may include circuitry for driving a pair of headphones or one or more speakers. Such circuitry often includes a power amplifier for driving an audio output signal to headphones or speakers. Oftentimes, such power amplifier is implemented using, in addition to other circuit elements (e.g., operational amplifiers, etc.), variable impedances (e.g., electrical resistances) to set a controllable gain of the power amplifier. In traditional approaches, such variable electrical resistances are implemented using a chain of series-coupled resistive elements with a plurality of gain switches each configured to electrically bypass a particular number of the resistive elements. However, such approaches may have disadvantages, including possible overstressing of the gate nodes of gain switches, especially as device feature sizes of integrated circuits shrink over time.